title: Frequency of EGFR and KRAS mutations in patients with non small cell lung cancer by racial background: do disparities exist?
abstract: BACKGROUND
  Mutations in EGFR and KRAS can impact treatment decisions for patients with NSCLC. The incidence of these mutations varies, and it is unclear whether there is a decreased frequency among African Americans (AfAs).
  
  
  METHODS
  We performed a retrospective chart review of 513 NSCLC patients undergoing EGFR and KRAS mutational analysis at the Hospital of the University of Pennsylvania between May 2008 and November 2011. Clinical and pathologic data were abstracted from the patients' electronic medical record.
  
  
  RESULTS
  Of 497 patients with informative EGFR mutation analyses, the frequency of EGFR mutation was 13.9%. The frequency of EGFR mutations was associated with race (p < 0.001) and was lower in AfA patients compared to Caucasian (C) patients but did not reach statistical significance (4.8% vs. 13.7%, p = 0.06). Mean Charlson Comorbidity Index and number of cigarette pack years were significantly lower in patients with EGFR mutations (p = 0.01 and p < 0.001, respectively). Multivariable logistic regression analysis showed a significant association between race and EGFR mutation (p = 0.01), even after adjusting for smoking status (p < 0.001) and gender (p = 0.03). KRAS mutation (study frequency 28.1%) was not associated with race (p = 0.08; p=0.51 for Afa vs. C patients), but was more common among smokers (p < 0.001) and females (p = 0.01).
  
  
  CONCLUSIONS
  Based on multivariable analysis, even after adjusting for smoking status and gender, we found that race was statistically significantly associated with EGFR mutation, but not KRAS mutational status. To the best of our knowledge, this is the largest single institution series to date evaluating racial differences in EGFR and KRAS mutational status among patients with NSCLC.
authors.affiliation: Abramson Cancer Center, Hospital of University of Pennsylvania, Philadelphia, PA, United States; Department of Medicine, Hospital of University of Pennsylvania, Philadelphia, PA, United States.
authors.forename: Joshua
authors.initials: J
authors.lastname: Bauml
authors.affiliation: Department of Biostatistics and Epidemiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, United States.
authors.forename: Rosemarie
authors.initials: R
authors.lastname: Mick
authors.affiliation: Department of Medicine, Hospital of University of Pennsylvania, Philadelphia, PA, United States.
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Pathology and Laboratory Medicine, Hospital of University of Pennsylvania, Philadelphia, PA, United States.
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Watt
authors.affiliation: Abramson Cancer Center, Hospital of University of Pennsylvania, Philadelphia, PA, United States; Department of Medicine, Hospital of University of Pennsylvania, Philadelphia, PA, United States.
authors.forename: Anil
authors.initials: A
authors.lastname: Vachani
authors.affiliation: Abramson Cancer Center, Hospital of University of Pennsylvania, Philadelphia, PA, United States; Department of Medicine, Hospital of University of Pennsylvania, Philadelphia, PA, United States.
authors.forename: Charu
authors.initials: C
authors.lastname: Aggarwal
authors.affiliation: Abramson Cancer Center, Hospital of University of Pennsylvania, Philadelphia, PA, United States; Department of Medicine, Hospital of University of Pennsylvania, Philadelphia, PA, United States.
authors.forename: Tracey
authors.initials: T
authors.lastname: Evans
authors.affiliation: Abramson Cancer Center, Hospital of University of Pennsylvania, Philadelphia, PA, United States; Department of Medicine, Hospital of University of Pennsylvania, Philadelphia, PA, United States.
authors.forename: Corey
authors.initials: C
authors.lastname: Langer
mesh_terms: D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics*; D066246:ErbB Receptors / Q000235:genetics*; D005006:Ethnicity / Q000235:genetics; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D059645:Mutation Rate; D016017:Odds Ratio; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D016283:Proto-Oncogene Proteins p21(ras); D012307:Risk Factors; D018631:ras Proteins / Q000235:genetics*
chemical_list: C117307:KRAS protein, human; D011518:Proto-Oncogene Proteins; D066246:ErbB Receptors; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins
keywords: EGFR; KRAS; NSCLC; Racial disparity